I was exposed to a hazardous chemical at work, burning half my back, both sides of my back side and down both my back legs stops behind my knees,.

I would recommend you contact a work injury lawyer in your area ASAP. Work comp laws and case values can vary greatly from state to state. Further, there could be notice requirements that need to be complied with in Alabama, or in whichever state that your work injury claim can be pursued.  Disclaimer: Please be advised that this response does not create an attorney-client relationship, and you should contact a lawyer licensed in your state to discuss your specific situation.